The present invention relates to a seal assembly, and more particularly to a shaft seal for an axle assembly.
A shaft extending through a housing often require resilient seals between the shaft and the housing through which it extends. One such housing mounts a carrier shaft that provides rotational drive to a differential of an axle. The shaft extends through the housing and is supported on bearings within. The interior of the housing is filled with a lubricant to insure proper operation of the internal components.
There are extreme differences between the interior environment of such a housing and the exterior environment in which the axle resides. That is, operating conditions may require that the seal between the shaft and the bearing housing inhibit water, air, dirt particles or other foreign objects from contaminating or otherwise deteriorating the lubricant content within the bearing housing while the exterior of the axle is subject to very harsh environmental factors.
Complex seals such as triple lip seals are typically utilized to provide an effective oil seal between the relatively rotating spindle shaft and the housing. Triple lip seals include multiple complex outer components such as slingers to protect the relatively more delicate internal fluid seal components. Such seals are complex to manufacture and rather expensive to produce.
Accordingly, it is desirable to provide a robust seal for a rotating shaft to prevent foreign objects from contaminating the lubricant content within the housing while minimizing the relatively more delicate internal components.
The seal assembly according to the present invention separates the extreme differences between the interior environment of a housing such as a differential and the exterior environment to which the housing is exposed. The seal assembly retains lubricant within the housing while preventing external contaminants from entering adjacent a rotating shaft.
The seal assembly includes an outer member, an inner member, and a resilient member therebetween. The resilient member is located between an inner diameter of the outer member and an outer diameter of the inner member. The resilient member includes substantially V-shaped or opposed parabolic members in cross-section which define a cavity therebetween. The parabolic members engage the outer diameter of the inner member and xe2x80x9cwipexe2x80x9d the outer diameter of the inner member as the inner member rotates relative to the resilient member. The cavity formed between the parabolic members is filled with the hydrophobic material to provide a barrier to undesirable moisture, lubricate the interface between the parabolic members and the outer diameter of the inner member, and further minimize ingestion of contaminants.
The present invention therefore provides a robust seal for a rotating shaft to prevent foreign objects from contaminating the lubricant content within the housing.